>>787
int[] nums = new int[10];
for (int i = 0; i < nenrei.length && nenrei[i] >= 0; i++) {
nums[nenrei[i] / 10]++;
}
for (int i = 0; i < nums.length; i++) {
System.out.printf("%2d代:%3d人%n", i * 10, nums[i]);
}